PathVisio (www.pathvisio.org) is a pathway visualization and analysis tool that has been used to create pathway maps, perform pathway statistics or visualize biological data on pathways. The visualization options in PathVisio are extensive, including color gradient and rule-based visualization options. Users can visualize single experiments, time-series data or even multiple datasets of various types like transcriptomics, proteomics and metabolomics together in the pathway. Recently, PathVisio introduced the visualization of data on interactions, providing a framework to visualize experimental or simulated modeling results on pathway diagrams. Biological pathways are not closed systems; they are linked to each other building larger biological networks. The WikiPathways app for Cytoscape (www.cytoscape.org), a network visualization and analysis software, allows users to open pathways as biological networks. Cytoscape 3 introduces a powerful and flexible visualization manager that allows users to control many visual properties to present biological data. This poster will show some of the features of PathVisio and Cytoscape for visualizing complex data on biological pathways.